The present invention relates generally to a method and apparatus for measuring distance and determining direction in a fluid medium. More particularly, the invention pertains to the measurement of distance and determination of direction in a liquid. Still more particularly, the invention provides a navigational method and apparatus for divers and aquanauts to help them determine the distance between two or more points underwater, and to determine the azimuth or relative direction in which a diver should travel to reach a particular reference point.
Underwater navigation for divers, aquanauts, etc. requires that at least two primary elements of information be available to the user--that of azimuth or relative direction to some reference point and that of range to that point. Various investigators have invented means to supply these two primary needs.